This invention relates to an electronic compass and method for determining the angle relative to the direction of the magnetic flux lines of the earth's magnetic field in a local area.
Presently available electronic compasses have relatively low accuracy. For example, a compass presently available as an option on some automobiles displays directions such as NE, SE, etc. Such a device, which uses a flux gate system for determining heading of the compass, is not very accurate and is thus unacceptable for applications in which high accuracy is required, e.g., airplanes. Hall effect devices have been suggested to improve the accuracy of electronic compasses. However, the resolution of such compasses has been very poor and compasses have not achieved better than one degree accuracy.
Other presently available devices are adversely effected by the near proximity of ferrous materials. This effect causes a deviation error which, if not corrected, results in inaccurate readings. The compasses described above have not solved the adverse effects of proximate ferrous objects.